McLaren M7A

Bruce McLaren Motor Racing was founded in 1963, with Bruce McLaren initially a factory driver for Cooper. Since 1966, the team had been building and racing their own Formula One cars, but their first two seasons yielded limited success – six points scored over two years, with a best result of fourth place. A key problem was the lack of a suitable engine; the 1966 M2B car used underpowered Ford and Serenissima V8 engines, and the 1967 M5A didn’t receive its British Racing Motors V12 until mid-season. In 1967, Cosworth debuted their DFV engine, initially supplied exclusively to Lotus, where it proved immediately successful. By 1968, the DFV became available for purchase, and McLaren acquired five engines at a cost of 7,500 pounds sterling each. Designer Robin Herd was recruited to the team in 1965, having previously worked as an aerospace engineer on the Concorde project at the National Gas Turbine Establishment (NGTE). Gordon Coppuck, another ex-NGTE employee, assisted Herd. Herd began the design of the M7A towards the end of 1967 but left to join Cosworth before its completion, leaving Coppuck and Bruce McLaren to finish the work.

The M7A was an open-wheeled, mid-engined single-seater. The chassis was a bathtub-type monocoque initially constructed from 22-gauge aluminium alloy panels glued and riveted to three steel bulkheads. Magnesium alloy was used for the dash panel, battery cover, and smaller non-stressed panels. The monocoque terminated behind the driver’s seat, with the engine acting as a stressed member bolted directly to the rearmost bulkhead. The gearbox was attached behind the engine, and the rear suspension – consisting of lateral top links, twin radius arms, and reversed wishbones – connected to the gearbox and rear bulkhead. The front suspension – upper and lower lateral links and radius arms – and the steering column were attached to the two bulkheads in front of the driver. Coilover springs and Koni dampers were initially used front and rear, later replaced by Armstrong units.

The outer bodywork consisted primarily of the monocoque, supplemented by glass-reinforced plastic (GRP) panels for the nose and cockpit, and sometimes a GRP engine cover. The wheelbase of the prototype car (M7A/1) was 7ft 9.6", with subsequent versions (M7A/2 and M7A/3) measuring 96.5", just 0.5" longer than the M5A. The front track was 58 inches (1,500 mm) and the rear track 57 inches (1,400 mm); the car weighed 1,140 pounds (520 kg). McLaren used their own magnesium alloy wheels, 15-inch (380 mm) diameter at the rear and 15- or 13-inch (330 mm) diameter at the front. Fuel was stored in tanks running along the sides of the chassis, above the driver’s legs and behind their seat, with a total capacity of 40 imperial gallons (180 L). For the first two championship races, Bruce McLaren’s car was fitted with outboard "pannier" fuel tanks at the side of the cockpit, based on a theory that sports racing cars’ handling was superior due to fuel weight distribution – an idea developed in discussion with Lotus boss Colin Chapman. The car was rebuilt without these pannier tanks after damage at the 1968 Monaco Grand Prix.

The prototype car initially used 10.5-inch (266.7mm) solid disc brakes with Girling calipers while awaiting delivery of a newly commissioned brake system. This new system, supplied by Lockheed (when most British teams used Girling), featured ventilated discs and four-piston lightweight alloy calipers with larger 11.625-inch (295mm) diameter discs. Ventilated discs, thicker in section with a hollow area for cooling, had previously been tried by Lotus but suffered from cracking. McLaren hoped their discs, mounted well within the wheels, would maintain a more constant temperature. During the 1968 season, wings began to appear on Formula One cars, and teams experimented with various configurations, regulated by the governing body, the CSI. McLaren had experimented with wings on their 1965 M2A but didn't use them on the 1967 M2B. The M7A and its variants used a variety of wing configurations throughout its racing history. The engine was a Cosworth DFV, a 90-degree V8 with aluminium alloy block and iron cylinder liners, producing 410 bhp (306 kW) at 9,000 rpm. It used a Hewland DG300 gearbox. The works cars were painted Traffic Yellow (British Standard colour 368 on the 381C scale), later incorrectly referred to as papaya orange, but known internally as McLaren Orange.

For the 1968 Formula One season, Bruce McLaren was partnered by Denny Hulme, the reigning world champion with Brabham. Hulme had also raced for McLaren in Can-Am. At the opening round in South Africa, only Hulme competed, finishing fifth in the M5A. The M7A debuted at the Race of Champions at Brands Hatch, where McLaren won from pole position, with Hulme third. Another victory followed at the non-championship BRDC International Trophy at Silverstone), with Hulme winning and McLaren second. In the M7A’s championship debut in Spain, Hulme was second and McLaren retired. At Monaco, McLaren crashed and Hulme finished fifth. The Belgian Grand Prix saw McLaren and Hulme qualify fifth and sixth. Hulme took the lead but retired with a half-shaft failure. McLaren then took the lead and won, becoming the second driver, after Jack Brabham, to win in a car bearing their own name.

Following the Belgian victory, McLaren’s Goodyear tyres lost competitiveness, and the team fell behind Lotus and Matra. At the Dutch Grand Prix, McLaren crashed, and Hulme retired. After initial experimentation with wings by Lotus, Ferrari and Brabham, McLaren fitted a rear wing for the French Grand Prix, but it was less effective than Lotus’s suspension-mounted design. Hulme finished fourth in France and fifth in Britain. An improvement came at the Italian Grand Prix where the cars ran without wings and Goodyear brought their new G9 specification tyre. McLaren qualified on the front row and led initially before slowing at the scene of an accident. Hulme went on to win. From the Canadian Grand Prix onwards, Dan Gurney drove a third M7A, his Anglo American Racers team having lost funding for their Eagle cars. Gurney retired in Canada, but Hulme and McLaren won in Canada, after their rivals had retired. Hulme was then jointly leading the Drivers’ Championship with two races remaining. He retired in the United States Grand Prix with mechanical failures, while McLaren finished sixth. In the final race in Mexico, McLaren finished second, but Hulme crashed, allowing Graham Hill to win the Drivers’ Championship.

In 1969, McLaren designed the new four-wheel-drive M9A, but continued to use the M7A while it was being developed. The M9A proved unsuccessful. Hulme scored a podium with the M7A at the South African Grand Prix. McLaren used the M7B version. Colin Crabbe Antique Automobiles bought the M7B, and Vic Elford drove it at the Dutch Grand Prix, finishing tenth. McLaren was fourth, third and third at the French, British and German Grands Prix respectively, but Hulme retired in each due to mechanical failure. Elford finished fifth in France but crashed and destroyed the M7B at the Nürburgring. The Italian Grand Prix saw McLaren finish fourth. Hulme won the final race of the year in Mexico. In 1970, the M7 had one final works outing with Dan Gurney at the British Grand Prix. Privateer John Surtees bought the M7C as a temporary solution until his Surtees TS7 was ready, racing it at four Grands Prix. Jo Bonnier later acquired the car and used it in two more races. The M7D was used intermittently with the M14D by Andrea de Adamich and Nanni Galli, starting only one race, the French Grand Prix. By 1971, Bonnier was the only entrant using an M7C, racing it at five races with a best finish of tenth in the Italian Grand Prix.

During the 1968 season, as teams began experimenting with wings, the governing body of the sport, the CSI, regulated their use. Later in the season, at the Monaco Grand Prix, the CSI banned wings altogether.

The M7A was the first McLaren to be powered by the Cosworth DFV engine, which went on to be used by the team until 1983. The M7B was a development of the M7A, with outboard fuel tanks, and the M7C was effectively a Formula 5000 M10A chassis adapted to fit the DFV engine.